The present invention relates to an air cleaner for the removal of pollutants from an air flow with a filter module, the filter module of which comprises at least one permeable filter layer for the accumulation of pollutants on the filter layer.
WO 2007/028176 A1 describes an air cleaner for cleaning machine exhaust air, the air cleaner of which has a filter module to remove non-air ingredients. Said filter module comprises several filter layers arranged one after another in the air flow to be cleaned. Each of these layers consists of several filter bars which are parallel but distant from each other wherein the mentioned filter bars are alternatingly set in the successively arranged filter layers in transverse position to the flow direction so that the air flow can take a serpentine-shaped way through the filter module. Said filter bars thereby consist of a porous material such as plastic foam, which is dampened by a fluid such as silicone oil so that non-air and/or undesired ingredients can be extracted from the air flow very effectively.
However, in the course of operation, such machines are susceptible to pollutant accumulations, which can occur very fast and/or after a relatively short time if the machine is used in highly contaminated air. No only microparticles can be accumulated on the air-permeable filter layers, but also bulkier pollutants such as dust fluff or even insects and leaves, which do not pass through the small spaces between the filter bars, especially on the serpentine-shaped way in case of alternatingly arranged filter bars. In addition, the ab- and/or adsorbed microparticles can agglomerate filter cake pieces after some time, which can clog the filter module and/or the filter layer. With increasing layer thickness of the filter cake, there is an improved extraction/accumulation effect but at the same time the negative effect of an increasing flow resistance of the clogging filter layer can be seen. The latter leads to an increasing performance requirement in terms of filter permeability and/or—in case of limited performance of a used air flow generation drive—to a continuous reduction of the volume flow through the filter.